Chemical Criteria

Criteria Review of Chloride, Sulfate and Total Dissolved Solids
Recently, the DNR began to compile all research related to toxicity of chloride, sulfate and total dissolved solids. The purpose was to update and develop criteria for these parameters to better protect aquatic life based on new scientific information.

Iron:
No numerical criteria have been adopted in Iowa’s Water Quality Standards for iron since there are no iron national criteria. IDNR recommends the use of a total iron concentration of 1 mg/l for the implementation of general criterion.